This study is focused on the relationship between children's adjustment in and outside of school and discontinuity in their lives. Children are studied in transition from elementary school to middle or junior high school and from childhood to early adolescence. Children's adjustment in school before transition and their ability to withstand the stress of the many changes they encounter during transition are examined in children's self-reports and reports from their teachers and peers. Measures include (a) children's perceptions and teachers' ratings of their cognitive, social, physical and general competence, (b) children's self-image, and (c) children's peer relations in school. They are examined in relation to (a) indices of children's physical maturity, (b) teachers' ratings of children's academic standing, and (c) children's perceptions of their school environment. For a group of children, adjustment and ability to withstand the stress of these changes are examined also as a function of their lives outside of school, primarily their family and peer relationships.